Improvement in burglar-alarms



G. P. BUSBY. Burglar-Alarm.

No. 200,372. Patented Feb. 19, 1878.

UNITED STATES PATENT OFFICE.

GEORGE F. BUSBY, OF LYNN, MASSACHUSETTS.

IMPROVEMENT IN BURGLAR-ALARMS.

Specification forming part of Letters Patent No. 00,372, dated February 19, 1878 application filed April 19, 1877.

To all whom it may concern.-

Be it known that I, GEORGE F. BUSBY, of Lynn, in the county of Essex and State of Massachusetts, :have invented a new and use- I ful Improvement on Burglar-Alarms, of which the following is a full, clear, and accurate description, reference being had to the figures and letters on the accompanying drawings, making part of this specification.

This invention relates to that class of burglar-alarms which are actuated by the uncoiling of a spring through a train of wheels; and it consists, mainly, in the construction, combination, and arrangement of the braking, tripping, and alarming devices, as and for the purposes hereinafter set forth and claimed.

In the accompanying drawings, Figure 1 represents a side elevation of my burglaralarm. Fig. 2 isan end view of the same.

Fig. 3 represents a cross-section through Fig.-

1 on the line 00 y, part of the casing being removed.

A designates the casing of my burglaralarm, which casing has an approximately triangular shape, and is open at the sides to allow the inspection of the alarm-works within. One end of said casing incloses an alarm-bell, K. (Indicated by dotted lines in Fig.1.) This bell is struck by a hammer, I, which is carried by a bent rod, D, depending in the usualmanher from the axis of the escapement-pallets which govern the motion of a train of wheels ending in Verge-wheel H. Main wheel P is actuated by a mainspring, R, of the usual construction. This mainspring is wound by means of a milled head, M, on the outer end of the winding-arbor. When thus wound and left free to operate the above-described train of wheels and escapement maintain a continuous ringing of bell K by hammer I.

The above devices .are, however, usually locked by means of a detent, 0, attached to or formed with a spring, F, and pressed thereby into engagement with said hammer-rod D.

B designates a trigger, pivoted at its upper end in the upper part of a vertical slot in casing A, and having attached to it below its pivotal point one end of a horizontally-operating rod, L, which extends through slot a in said casing.

The arrangement of said trigger B is such that a draft on said operating-rod will pull said trigger against said detent and spring, so as to draw said detent away from said hammer-rod and free the latter. The same result may be effected by pressure against the back or outer side of said trigger B.

This alarm may be used either with doors or windows, and may have a cord-connection therewith, so that the opening of the door or the raising or lowering of a sash will cause a pull on rod L. The burglar-alarm may also be attached to one sash of a window, and a stud or screw fastened to the other sash thereof, so that when either sash is moved vertically the said stud or screw will come into contact with the back of said trigger, tripping said detent, with the result described.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

In combination with casing A, slotted on opposite sides at a and a, trigger B, rod L,

detent 0, spring F, and the alarm mechanism, substantially as set forth.

GEORGE F. BUSBY.

Witnesses GHAs. Y. MANN, THOMAS D. GARD. 

